MC Fan not working

I enclosed my P1P a couple of months ago and I followed BL’s advice about installing the MC Fan for enclosed printers.
I bought the stock MC fan from BL, installed it and connected it to where their instructions say.

I added the G-code to Machine Start G-code as directed:
“M710 A1 S255 ; turn on the automatic control of the MC fan,the MC fan will automatically turn on when the stepper motor is turned on and turn off when the stepper motor is turned off”

I never verified it was actually running until I went to install the chamber exhaust fan. I decided to watch the MC fan while it printed and I have not seen it run once.

P1P firmware: 1.5.2.0

I checked the connector and it’s seated correctly.

Any idea why it’s not running?